Resonance in series rlc circuit pdf resonance in series rlc circuits. To investigate resonance phenomena that result from forced motion near a systems natural frequency. Experiment 10 rlc series circuit resonance in an rlc series circuit objective. As all the three elements are connected in series so, the current flowing in each element of the circuit will be same as the total current i flowing. L resonance occurs when the voltage and current at the input terminals are in phase. Simple series and parallel lc circuit resonance operation. Electrical resonance occurs in an electric circuit at a particular resonant frequency when the. And finally, a series lc circuit with the significant resistance in parallel with the capacitor the shifted resonance is shown below. In actual, rather than ideal components, the flow of current is opposed, generally by the resistance of the windings of the coil. Series lc resonant circuit with resistance in parallel with c. In a series resonance lc circuit configuration, the two resonances x c and x l cancel each other out. Resonance circuit introduction thus far we have studied a circuit involving a 1 series resistor r and capacitor c circuit as well as a 2 series resistor r and inductor l circuit.
Figure 1 shows a driven rlc circuit where vo is the applied sinusoidal voltage from the function generator and v is the voltage measured across the resistor using an oscilloscope. Power amplifier, voltage sensor, capacitor 100 f, inductor coil and iron core, resistor. Resonance can occur in something called an rlc circuit. These are devices which convert electrical energy into thermal energy. Thus far we have studied a circuit involving a 1 series resistor r and capacitor c circuit as well as a 2. Voltage is at a peak at resonance since voltage is proportional to impedance eiz. The circuit vibrates and may produce a standing wave, depending on the frequency of the driver, the wavelength of the oscillating wave and the geometry of the circuit. At resonance there will be a large circulating current between the inductor and the capacitor due to the energy of the oscillations, then. Resonance in parallel rlc circuit linkedin slideshare. To experimentally determine the resonance frequency in a series rlc circuit and compare this to the expected resonance value. Above and below resonance, the current decreases because the impedance increases.
The current flowing through the resistor, i r, the current flowing through the inductor, i l and the current through the capacitor, i c but the current flowing through each branch and therefore each component will be different to. A more selective circuit will have a narrower bandwidth whereas a less selective circuit will have a wider bandwidth. P517617 lec4, p5 there is an exact analogy between an rlc circuit and a harmonic oscillator mass attached to spring. The name rlc circuit is derived from the starting letter from the components of resistance, inductor, and capacitor. You can also vary the frequency of the source of alternating. The steadystate admittance offered by the circuit is.
The letters stand for the different parts of the circuit. An rlc circuit is an electrical circuit it consists of a resistor, inductor, and capacitor they are represented by the letters r, l and c. Resonance in ac circuits pdf version 2 ee iit, kharagpur. Parallel rlc circuit and rlc parallel circuit analysis. In both cases, it was simpler for the actual experiment to replace the battery and switch with a signal generator producing a square wave. Physics 14 lab manual a resonant circuit page 3 if we start with some charge q 0 on the capacitor, we expect qt q 0 cos. A parallel circuit containing a resistance, r, an inductance, l and a capacitance, c will produce a parallel resonance also called antiresonance circuit when the resultant current through the parallel combination is in phase with the supply voltage. The rlc series circuit is defined as when a pure resistance of r ohms, a pure inductance of l henry and a pure capacitance of c farads are connected together in series combination with each other.
The series rlc resonance circuit introduction thus far we have studied a circuit involving a 1 series resistor r and capacitor c circuit as well as a 2 series resistor r and inductor l circuit. Rlc series circuit when a pure resistance of r ohms, a pure inductance of l henry and a pure capacitance of c farads are connected together in series combination with each other then rlc series circuit is formed. In electrical science impedance of the inductors and capacitors depends on the frequency. Indicate the resonance frequency f o and the width of the resonance curve the bandwidth, which is the interval. If we consider an example of a series resonant circuit.
Chapter 21 19 power in ac circuits ipower formula irewrite using icos. How to build an lc resonant circuit hacked by 4lf45t. Both are 3element networks that contain two reactive components making them a secondorder circuit, both are influenced by variations in the supply frequency and both have a frequency point where their two reactive components cancel each other out influencing. Physics 14 lab manual a resonant circuit page 5 in the lab, well study this by driving the circuit with a relatively lowfrequency square wave the abrupt change in the driving voltage is just like closing a switch, and the circuit rings in response. Electrical tutorial about series resonance and the series rlc resonant circuit with resistance, inductance and capacitance connected in series. Therefore at the resonant frequency the impedance seen by the source is purely resistive. In the physics of coupled oscillators, antiresonance, by analogy with resonance, is a pronounced minimum in the amplitude of an oscillator at a particular frequency, accompanied by a large, abrupt shift in its oscillation phase. To understand the idea of resonance, and to determine the behavior of current and voltage in a driven rlc circuit above, below and at the resonant frequency prelab reading.
So far, the phenomenon of resonance appears to be a useless curiosity, or at most a nuisance to be avoided especially if series resonance makes for a shortcircuit across our ac voltage source. But the transient response is only part of the story. Example of a simple tank lc circuit what is the total impedance of the circuits. Current in a parallel resonance circuit at resonance the current flowing through the circuit is at its minimum as the inductive and capacitive branch currents are equal il ic and are 180o out of phase. Jun 08, 2019 since resonance in series rlc circuit occurs at particular frequency, so it is used for filtering and tuning purpose as it does not allow unwanted oscillations that would otherwise cause signal distortion, noise and damage to circuit to pass through it. Series resonance circuits are useful for constructing highly frequency selective filters. The voltages across l and c are maximum at resonance, but they are also equal in magnitude. However, its high current and very high component voltage values can cause damage to the circuit. The series resonance rlc circuit is shown in the figure below. Rlc resonance circuit here we have an applet with a very basic rlc circuit with an external source of alternating current. An lc resonant circuit is a circuit that is composed of a single inductor and capacitor that can do many powerful and useful things. In many ways a parallel resonance circuit is exactly the same as the series resonance circuit we looked at in the previous tutorial.
I was wondering if it is possible set up a circuit where you use a ac sine wave at the resonant frequency of the circuit and limit the current from the ac source to maybe the low ma range. Determining the resonance frequency for series rlc circuits duration. Resonant circuits measuring inductance frederiksen. Piot, phys 375 spring 2008 the same formalism as before can be applied to parallel rlc circuits. Sensitive radiofrequency measurement of a quantum dot by. Rlc resonant circuits andrew mchutchon april 20, 20 1 capacitors and inductors there is a lot of inconsistency when it comes to dealing with reactances of complex components. The assignment draws from chapters 610 of your text. Pdf simulation of rlc series and parallel resonance in. A resonant circuit can be used to block present high impedance toward a frequency or range of frequencies, thus acting as a sort of frequency. To explore the time dependent behavior of rlc circuits, both driven with an ac function generator and undriven 2. Lets continue the exploration of the frequency response of rlc circuits by investigating the series rlc circuit shown on figure 1. The most prominent feature of the frequency response of a resonant circuit is a sharp resonant peak in its amplitude characteristics. At resonance, the reactances cancel out leaving just a peak voltage, vpk, across the loss resistance, r.
Since i is maximum, the power dissipated would be maximum. In electrical engineering, antiresonance is the condition for which the reactance vanishes and the impedance of an electrical circuit is very high, approaching infinity in an electric circuit consisting of a capacitor and an inductor in parallel, antiresonance occurs when the alternating current line voltage and the resultant current are in phase. Rlc series and parallel circuit at resonance is a part of basic electrical engineering course which is mandatory for all discipline students to aware the idea of resonance in all technical. Circuit theoryrlc circuits wikibooks, open books for an. Applications of resonance resonance electronics textbook.
Connections to function generator and oscilloscope. Frequency response of rlc resonance circuit, from eq. You are already familiar with the concept of resonance. A series resonant circuit has the capability to draw heavy current and power from the mains. Another use for resonance is in applications where the effects of greatly increased or decreased impedance at a particular frequency is desired. The name of the circuit is derived from the letters that are used to denote the constituent components of this circuit, where. The selectivity of a series resonance circuit can be controlled by adjusting the value of the resistance only, keeping all the other components the same, since q x l or x cr. Rlc circuit at the series resonant frequency, the current is maximum i max v s r. Also adjust l1 and or c1 to tune the exact frequency of the resonance. Where zr is the resonance impedance of the circuit. You can think of resonance as just the right frequency achieved so that the output signal reaches a perfect state of oscillations. Displayed is then the frequency response of the current in this circuit.
Sketch the so called resonance curve for the series resonance circuit in fig. Calculate these numbers for specific component values which you may use in the laboratory, for example. The format followed in this document is as follows. This implies that at resonance the inductorcapacitor combination. Electrical resonance occurs in an electric circuit at a particular resonant frequency when the impedances or admittances of circuit elements cancel each other. For a series rlc circuit at certain frequency called resonant frequency, the following. Design of resonant clock distribution networks for 3d integrated. The most common condition in which it causes disturbances is when the magnetizing impedance of a transformer is placed in series with a system capacitor. The voltage v r measured across the resistor of the rlc series circuit are predicted to look like this. The name of the circuit is derived from the letters that are used to denote the constituent components of this circuit, where the sequence of the components may vary from rlc. An rlc circuit is an electrical circuit consisting of a resistor r, an inductor l, and a capacitor c connected in series or in parallel. In the above parallel rlc circuit, we can see that the supply voltage, v s is common to all three components whilst the supply current i s consists of three parts. That means that a signal around 1 mhz will get amplified by a factor of about 63x 103620.
At a resonant frequency, the reflection coefficient is highly sensitive to the device conductance. None of these limits are exceeded in the circuits described in this manual. Here we have an applet with a very basic rlc circuit with an external source of alternating current. In some circuits, this happens when the impedance between the input and output of the circuit is almost zero and the transfer function is close to one resonant circuits exhibit ringing and can generate higher voltages and currents. The purpose of this laboratory activity is to study resonance in a resistorinductorcapacitor rlc circuit by examining the current through the circuit as a function of the frequency of the applied voltage. If the external vibration is equal to the natural frequency resonance occurs. May 27, 2014 voltage is at a peak at resonance since voltage is proportional to impedance eiz. You can think of resonance as just the right frequency achieved so. This corresponds to a purely real admittance, so that the necessary condition is given by. Resonant circuits series or parallel are used in many applications such as. Necessary for resonance in the above circuits are derived. Put on the vertical axis the current or voltage across resistor r and log f on the horizontal axis. You can change the resistance, the capacitance, and the inductance of the circuit. The voltage through an rlc series circuit will be measured as a function of frequency for a fixed applied voltage.
Such frequencies are known as the systems antiresonant frequencies, and at these frequencies the oscillation amplitude can drop to almost zero. The temr ferro resonance refers to a special kind of resonance that involves capacitance and ironcore inductance. In a very similar way one can show that a series lc circuit behaves as a short circuit when driven on resonance i. Parallel resonance and parallel rlc resonant circuit. Resonance in this circuit occurs because energy is stored in two different ways. Resonant circuit serves as stable frequency source. An lc resonant circuit, as the name implies, achieves resonance. In this case the system will be a variety of rlc circuits. Then you use a dc source across the inductor to provide. Operated at the resonant frequency using an efficiency optimal control, the series series compensation topology achieves the highest dctodc.
769 1297 768 721 1377 1000 478 667 262 211 1102 10 951 556 375 432 213 1272 661 1496 33 1277 275 1178 1424 115 912 305 1435 774 650 970 376 1442 1366 498 1374 832 590 842